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Candace M. Hogue Sunthud Pornprasertmanit Mary D. Fry Mijke Rhemtulla Todd D. Little 《Measurement in physical education and exercise science》2013,17(4):310-325
Salivary cortisol is often used as an index of physiological and psychological stress in exercise science and psychoneuroendocrine research. A primary concern when designing research studies examining cortisol stems from the high cost of analysis. Planned missing data designs involve intentionally omitting a random subset of observations from data collection, reducing both the cost of data collection and participant burden. These designs have the potential to result in more efficient, cost-effective analyses with minimal power loss. Using salivary cortisol data from a previous study (Hogue, Fry, Fry, & Pressman, 2013), this article examines statistical power and estimated costs of six different planned missing data designs using growth curve modeling. Results indicate that using a planned missing data design would have provided the same results at a lower cost relative to the traditional, complete data analysis of salivary cortisol. 相似文献
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Masayuki Konishi Masaki Takahashi Naoya Endo Shigeharu Numao Shun Takagi Masashi Miyashita 《Journal of sports sciences》2013,31(3):248-255
Abstract The aim of this study was to investigate the effects of sleep deprivation on autonomic and endocrine functions during the day and on exercise tolerance in the evening. Ten healthy young males completed two, 2-day control and sleep deprivation trials. For the control trial, participants were allowed normal sleep from 23:00 to 07:00 h. For the sleep deprivation trial, participants did not sleep for 34 h. Autonomic activity was measured from 19:00 h on day 1 to 16:00 h on day 2 by frequency-domain measures of heart rate variability. Endocrine function was examined by measuring adrenocorticotropic hormone and cortisol from venous blood samples collected on day 2 at 09:00, 13:00, and 17:00 h and immediately after an exercise tolerance testing. Autonomic regulation, particularly parasympathetic regulation estimated from the high-frequency component of heart rate variability analysis, was significantly higher in the sleep deprivation trial than in the control trial in the morning and afternoon of day 2. Plasma adrenocorticotropic hormone concentrations were significantly higher at 09:00 and 13:00 h of day 2 under sleep deprivation. Heart rate during exercise was significantly lower following sleep deprivation. Therefore, the effects of sleep deprivation on autonomic regulation depend on the time of the day. 相似文献
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John Hough Robert Corney Antonios Kouris Michael Gleeson 《Journal of sports sciences》2013,31(14):1614-1623
Abstract This study examined salivary cortisol and testosterone responses to two, different high-intensity, ～30-min cycles separated by 2 h rest before and after an 11-day intensified training period. Twelve recreationally active, healthy males completed the study. Saliva samples were collected before, immediately after and 30 min after both bouts with salivary cortisol and testosterone concentrations assessed. Compared with pre-training blunted exercise-induced salivary cortisol, testosterone and cortisol/testosterone responses to both bouts post-training were observed (P < 0.05 for all). Comparing pre- with post-training the absolute exercise-induced salivary cortisol, testosterone and cortisol/testosterone decreased from 11.1 to 3.1 and 7.0 to 4.4 nmol · L?1 (cortisol), from 407 to 258 and from 473 to 274 pmol · L?1 (testosterone) and from 12 to 4 and 7 to 5 (cortisol/testosterone) for the first and second bouts, respectively (P < 0.05). No differences in the pre- and post-training rating of perceived exertion (RPE) and heart rate (HR) responses during the cycles or times to fatigue were found (P > 0.05). Fatigue and Burnout scores were higher post- compared with pre-training (P < 0.05). These high-intensity exercise bouts can detect altered hormonal responses following intensified training. This test could assess an athlete's current hormonal status, reductions in salivary cortisol and testosterone responses suggestive of increased fatigue. 相似文献
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Morris Gellisch Oliver T. Wolf Nina Minkley Wolfgang H. Kirchner Martin Brüne Beate Brand-Saberi 《Anatomical sciences education》2022,15(5):811-826
To examine the implications of the transition from face-to-face to online learning from a psychobiological perspective, this study investigated potential differences in physiological stress parameters of students engaged in online or face-to-face learning and determined whether these can be identified as possible mediators between learning experience and achievement emotions. In a randomized experimental field study, medical students (n = 82) attended either regular face-to-face classes of the microscopic anatomy course or the same practical course online using Zoom videoconferencing platform. The present study investigated Heart Rate Variability (HRV) and salivary cortisol concentration as stress correlates, within the contexts of online and face-to-face learning and compared these parameters with a control group that was measured at rest. Additionally, participants completed a standardized questionnaire about their experienced emotions in relation to task achievement and subjective stress levels. A significant reduction in HRV was found in face-to-face learning, suggesting stronger stress responses in the face-to-face learning environment (η2 = 0.421, P < 0.001). Furthermore, participants engaged in face-to-face learning showed significantly higher cortisol concentrations (η2 = 0.115, P = 0.032). Additionally, increased sympathetic activation correlated with the discrete positive emotion of enjoyment exclusively within the face-to-face condition (r = 0.365, P = 0.043). These results indicate that the transfer of a face-to-face practical course in microscopic anatomy to an online learning environment is associated with decreased sympathetic and enhanced vagal cardiovascular influences, together with lower cortisol concentrations in healthy medical students. 相似文献
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Su Yeong Kim Wen Wen Shanting Chen Jinjin Yan Jiaxiu Song Minyu Zhang Katharine H. Zeiders 《Child development》2022,93(4):1106-1120
This study examined the associations of language brokering stress intensity and exposure with Mexican-origin youths’ cortisol responses when brokering for fathers and mothers, and the moderating role of youths’ brokering efficacy in these relations. Participants were 289 adolescents (Mage = 17.38, SD = .94, 52% girls) in immigrant families. When brokering for mothers, stress exposure was related to flatter (less healthy) same-day diurnal slopes in youth. When brokering for fathers, daily brokering efficacy buffered the detrimental link between stress intensity and youths’ same-day cortisol slopes. When brokering for fathers/mothers, stress intensity and exposure were related to flatter (less healthy) next-day diurnal slopes. Although daily brokering stress can relate to youth physiologic functioning, feeling efficacious about brokering may buffer the negative ramifications of stress. 相似文献
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《运动与健康科学(英文)》2014,3(4):279-283
PurposeThe purpose of this study was to evaluate the changes in some hormonal parameters (cortisol, testosterone, ratio of testosterone/cortisol (T/C)) in professional soccer players during a season.MethodsFifteen professional players from a soccer club of the first division of the Greek soccer league participated. All sport medical examinations were conducted four times: before the re-building period, post re-building period, mid-season, and after finishing the competition phase.ResultsFor testosterone, significant differences were observed between the end season and post re-building period (11.6%; p < 0.05) and mid-season (12.1%; p < 0.05). The cortisol concentration increased at mid-season by approximately 23%, and this change differed significantly from all other measurements for this hormone. The T/C ratio increased at the post re-building period and decreased at the middle of the season.ConclusionThese hormones and their ratios could be used as stress and recovery state indicators. Coaches can use these parameters in combination with other indicators to optimize workloads, and to avoid overreaching and overtraining. 相似文献
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力竭运动及慢性心理应激对血尿素氮和皮质醇的影响 总被引：1，自引：0，他引：1
通过建立心理应激和力竭运动动物模型,测定慢性心理应激和力竭运动后大鼠血清中血尿素氮的含量及皮质醇的含量,揭示运动及心理应激对免疫功能的影响。结论:力竭运动使血尿素氮升高,该实验运动模型的建立比较合理。慢性情绪应激基础上的力竭运动会引起皮质醇含量的显著升高,其可能的机理是情绪应激加上力竭运动,比单一的应激引起机体的应激状态更为明显。 相似文献
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赛艇运动员不同训练周期后免疫系统及部分血液生化指标变化的研究 总被引：1，自引：0，他引：1
观察湖北省划船队女子赛艇运动员(10人),在备战第10届全国运动会封闭训练期间,不同训练周期后血清免疫球蛋白指标IgA、IgG、IgM以及部分血液生化指标血红蛋白(Hb)、血尿素氮(BUN)、睾酮(T)、皮质醇(C)、T/C的水平,并进行相关分析.探讨赛艇运动员身体机能评定和训练监控更有效的方法和途径,探讨这些指标在不同训练周期后变化的某些内在规律. 相似文献
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长期运动训练对优秀女子中长跑运动员睾酮、皮质醇和睾酮／皮质醇比值的影响 总被引：7，自引：0，他引：7
观察长期运动训练对女子中长跑运动员的睾酮、皮质醇及睾酮/皮质醇比值变化的影响。对10名优秀女子中长跑运动员两年训练中的5个时间点的睾酮、皮质醇进行测试,实验方法为放射免疫法。女子中长跑运动员等级有提高的趋势;血清睾酮水平有下降再上升的趋势;皮质醇有下降的趋势;下降变化在整个时期内出现统计学意义,实验前后运动队睾酮/皮质醇比值有下降再上升的趋势。在长期训练时,优秀女子中长跑运动员机体出现对运动负荷不适应到适应的过程。 相似文献